On 3 May 2018 at 23:26, Paolo Cavallini <[email protected]> wrote: > Hi all, > the measurements of a EPSG:4326 line appear correct in any SRS, both > with the interactive info tool and writing on the table the value of > $length, *if* the OTF reprojection is active (including 4326). > If it is not, the result is grossly overestimated (298 m instead of 228, > etc.). > Am I missing something, or this is a serious bug?
It's not a bug as much as very confusing 2.x behavior. The obscure link between a "rendering" setting (OTF projection) and ellipsoidal calculations (area/distance) is extremely confusing for users. We couldn't change this in 2.x because of the API freeze and how embedded this logic was in many areas of QGIS code and API. That's why in 3.0 the whole OTF logic was reworked, so that OTF is always on for rendering and doesn't the choice of ellipsoidal calculations or not is totally based on the project's ellipsoid setting. So unfortunately for 2.18 there's really no choice but to ensure that OTF projection setting is enabled. Nyall _______________________________________________ QGIS-Developer mailing list [email protected] List info: https://lists.osgeo.org/mailman/listinfo/qgis-developer Unsubscribe: https://lists.osgeo.org/mailman/listinfo/qgis-developer
